Source/WebCore/rendering/svg/SVGRootInlineBox.cpp

/*
 * Copyright (C) 2006 Oliver Hunt <ojh16@student.canterbury.ac.nz>
 * Copyright (C) 2006 Apple Computer Inc.
 * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
 * Copyright (C) Research In Motion Limited 2010. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include "config.h"
#include "SVGRootInlineBox.h"

#if ENABLE(SVG)
#include "GraphicsContext.h"
#include "RenderBlock.h"
#include "RenderSVGInlineText.h"
#include "SVGInlineFlowBox.h"
#include "SVGInlineTextBox.h"
#include "SVGNames.h"
#include "SVGRenderSupport.h"
#include "SVGTextPositioningElement.h"

namespace WebCore {

void SVGRootInlineBox::paint(PaintInfo& paintInfo, int, int)
{
    ASSERT(paintInfo.phase == PaintPhaseForeground || paintInfo.phase == PaintPhaseSelection);
    ASSERT(!paintInfo.context->paintingDisabled());

    RenderObject* boxRenderer = renderer();
    ASSERT(boxRenderer);

    bool isPrinting = renderer()->document()->printing();
    bool hasSelection = !isPrinting && selectionState() != RenderObject::SelectionNone;

    PaintInfo childPaintInfo(paintInfo);
    if (hasSelection) {
        for (InlineBox* child = firstChild(); child; child = child->nextOnLine()) {
            if (child->isSVGInlineTextBox())
                static_cast<SVGInlineTextBox*>(child)->paintSelectionBackground(childPaintInfo);
            else if (child->isSVGInlineFlowBox())
                static_cast<SVGInlineFlowBox*>(child)->paintSelectionBackground(childPaintInfo);
        }
    }

    childPaintInfo.context->save();

    if (SVGRenderSupport::prepareToRenderSVGContent(boxRenderer, childPaintInfo)) {
        for (InlineBox* child = firstChild(); child; child = child->nextOnLine()) {
            if (child->isSVGInlineTextBox())
                SVGInlineFlowBox::computeTextMatchMarkerRectForRenderer(toRenderSVGInlineText(static_cast<SVGInlineTextBox*>(child)->textRenderer()));

            child->paint(childPaintInfo, 0, 0);
        }
    }

    SVGRenderSupport::finishRenderSVGContent(boxRenderer, childPaintInfo, paintInfo.context);
    childPaintInfo.context->restore();
}

void SVGRootInlineBox::computePerCharacterLayoutInformation()
{
    RenderBlock* parentBlock = block();
    ASSERT(parentBlock);

    // Build list of all text boxes which belong to our root renderer, in logical order,
    // aka. the order of the characters as they appear in the original document.
    // This is needed to maintain correspondence between the x/y/dx/dy/rotate value
    // lists and the potentially reordered characters in the inline box tree.
    Vector<SVGInlineTextBox*> boxesInLogicalOrder;
    buildTextBoxListInLogicalOrder(parentBlock, boxesInLogicalOrder);

    // Perform SVG text layout phase two (see SVGTextLayoutEngine for details).
    SVGTextLayoutEngine characterLayout(boxesInLogicalOrder);
    layoutCharactersInTextBoxes(this, characterLayout);

    // Perform SVG text layout phase three (see SVGTextChunkBuilder for details).
    characterLayout.finishLayout();

    // Perform SVG text layout phase four
    // Position & resize all SVGInlineText/FlowBoxes in the inline box tree, resize the root box as well as the RenderSVGText parent block.
    layoutChildBoxes(this);
    layoutRootBox();
}

void SVGRootInlineBox::buildTextBoxListInLogicalOrder(RenderObject* start, Vector<SVGInlineTextBox*>& boxes)
{
    bool ltr = start->style()->isLeftToRightDirection();
    for (RenderObject* child = start->firstChild(); child; child = child->nextSibling()) {
        if (child->isSVGInline()) {
            buildTextBoxListInLogicalOrder(child, boxes);
            continue;
        }

        if (!child->isSVGInlineText())
            continue;

        RenderSVGInlineText* text = toRenderSVGInlineText(child);
        for (InlineTextBox* textBox = ltr ? text->firstTextBox() : text->lastTextBox(); textBox; textBox = ltr ? textBox->nextTextBox() : textBox->prevTextBox()) {
            if (!textBox->isSVGInlineTextBox())
                continue;
            boxes.append(static_cast<SVGInlineTextBox*>(textBox));
        }
    }
}

void SVGRootInlineBox::layoutCharactersInTextBoxes(InlineFlowBox* start, SVGTextLayoutEngine& characterLayout)
{
    for (InlineBox* child = start->firstChild(); child; child = child->nextOnLine()) {
        if (child->isSVGInlineTextBox()) {
            ASSERT(child->renderer());
            ASSERT(child->renderer()->isSVGInlineText());

            SVGInlineTextBox* textBox = static_cast<SVGInlineTextBox*>(child);
            characterLayout.layoutInlineTextBox(textBox);
        } else {
            ASSERT(child->isInlineFlowBox());

            // Skip generated content.
            Node* node = child->renderer()->node();
            if (!node)
                continue;

            SVGInlineFlowBox* flowBox = static_cast<SVGInlineFlowBox*>(child);
            bool isTextPath = node->hasTagName(SVGNames::textPathTag);
            if (isTextPath) {
                // Build text chunks for all <textPath> children, using the line layout algorithm.
                // This is needeed as text-anchor is just an additional startOffset for text paths.
                Vector<SVGInlineTextBox*> boxesInLogicalOrder;
                buildTextBoxListInLogicalOrder(flowBox->renderer(), boxesInLogicalOrder);

                SVGTextLayoutEngine lineLayout(boxesInLogicalOrder);
                layoutCharactersInTextBoxes(flowBox, lineLayout);

                characterLayout.beginTextPathLayout(child->renderer(), lineLayout);
            }

            layoutCharactersInTextBoxes(flowBox, characterLayout);

            if (isTextPath)
                characterLayout.endTextPathLayout();
        }
    }
}

void SVGRootInlineBox::layoutChildBoxes(InlineFlowBox* start)
{
    for (InlineBox* child = start->firstChild(); child; child = child->nextOnLine()) {
        if (child->isSVGInlineTextBox()) {
            ASSERT(child->renderer());
            ASSERT(child->renderer()->isSVGInlineText());

            SVGInlineTextBox* textBox = static_cast<SVGInlineTextBox*>(child);
            IntRect boxRect = textBox->calculateBoundaries();
            textBox->setX(boxRect.x());
            textBox->setY(boxRect.y());
            textBox->setLogicalWidth(boxRect.width());
            textBox->setLogicalHeight(boxRect.height());
        } else {
            ASSERT(child->isInlineFlowBox());

            // Skip generated content.
            if (!child->renderer()->node())
                continue;

            SVGInlineFlowBox* flowBox = static_cast<SVGInlineFlowBox*>(child);
            layoutChildBoxes(flowBox);

            IntRect boxRect = flowBox->calculateBoundaries();
            flowBox->setX(boxRect.x());
            flowBox->setY(boxRect.y());
            flowBox->setLogicalWidth(boxRect.width());
            flowBox->setLogicalHeight(boxRect.height());
        }
    }
}

void SVGRootInlineBox::layoutRootBox()
{
    RenderBlock* parentBlock = block();
    ASSERT(parentBlock);

    IntRect childRect;
    for (InlineBox* child = firstChild(); child; child = child->nextOnLine()) {
        // Skip generated content.
        if (!child->renderer()->node())
            continue;
        childRect.unite(child->calculateBoundaries());
    }

    int xBlock = childRect.x();
    int yBlock = childRect.y();
    int widthBlock = childRect.width();
    int heightBlock = childRect.height();

    // Finally, assign the root block position, now that all content is laid out.
    parentBlock->setLocation(xBlock, yBlock);
    parentBlock->setWidth(widthBlock);
    parentBlock->setHeight(heightBlock);

    // Position all children relative to the parent block.
    for (InlineBox* child = firstChild(); child; child = child->nextOnLine()) {
        // Skip generated content.
        if (!child->renderer()->node())
            continue;
        child->adjustPosition(-xBlock, -yBlock);
    }

    // Position ourselves.
    setX(0);
    setY(0);
    setLogicalWidth(widthBlock);
    setLogicalHeight(heightBlock);
    setBlockLogicalHeight(heightBlock);
    setLineTopBottomPositions(0, heightBlock);
}

InlineBox* SVGRootInlineBox::closestLeafChildForPosition(const IntPoint& point)
{
    InlineBox* firstLeaf = firstLeafChild();
    InlineBox* lastLeaf = lastLeafChild();
    if (firstLeaf == lastLeaf)
        return firstLeaf;

    // FIXME: Check for vertical text!
    InlineBox* closestLeaf = 0;
    for (InlineBox* leaf = firstLeaf; leaf; leaf = leaf->nextLeafChild()) {
        if (point.y() < leaf->m_y)
            continue;
        if (point.y() > leaf->m_y + leaf->virtualLogicalHeight())
            continue;

        closestLeaf = leaf;
        if (point.x() < leaf->m_x + leaf->m_logicalWidth)
            return leaf;
    }

    return closestLeaf ? closestLeaf : lastLeaf;
}

} // namespace WebCore

#endif // ENABLE(SVG)